The purpose of this proposal is to develop a pediatric VAD (the CCF PediPump) that is based on a magnetic bearing supported, rotary dynamic pump that can provide support for the entire range of patient sizes encountered in pediatrics. The design of this pump features the absence of a seal with suspension of the rotor on magnetic bearings resulting in extremely high durability. A second, unique feature of this pump is its extremely small size measuring approximately 7 mm X 60 mm which imparts less than 10% of the physical displacement of the MicroMed DeBakey or Jarvik 2000 axial fiow pumps while retaining good flow capacity. In fact, the device is capable of providing pressure and flows capable of supporting adults, far exceeding requirements for support of children in the 2 to 25 kg weight range. In its present form, two packaging concepts wil be used based on patient size: an intravascuiar configuration will be used for older children while an extravascular configuration will be used for the smallest children. Because of its small size the PediPump provides the very real hope for long-term development of a totally implantable system for even the smallest infants. Further, this device is suitable for right ventricular support (RVAD), left ventricular support (LVAD) and biventricular support (BVAD). This device has high durability and superior biocompatibility with minimal host impact, including the potential for minimal or no anticoagulation, low levels of hemolysis and minimal infection risk. A single pump as described for this system is suitable for short-term support while being adaptable to ambulatory chronic circulatory support.